The 28-year-old native from Lewisville, North Carolina, will be returning to the Xfinity Series and make his first start with JGR at Daytona International Speedway in February.
The 18-year-old grandson of NASCAR owner Joe Gibbs will contend for the 2021 ARCA championship while making his Xfinity Series debut at Daytona RC in February.
The 26-year-old Ferguson from Lincolnton, North Carolina, will make his second career Truck start with Kaulig Racing more than a month after making his Truck debut at Bristol.
Spire Motorsports has earned one win and three top five finishes. Rajah Caruth took the checkered flag in last year's Rackley Roofing 200 after leading 61 laps.
In 12 previous NASCAR Cup Series starts at Nashville (Tenn.) Superspeedway, Spire Motorsports has two top-five finishes with a best result of second earned twice by Zane Smith (2024) and Carson Hocevar (2025).